<?php
/**
 * Zend Framework
 *
 * LICENSE
 *
 * This source file is subject to the new BSD license that is bundled
 * with this package in the file LICENSE.txt.
 * It is also available through the world-wide-web at this URL:
 * http://framework.zend.com/license/new-bsd
 * If you did not receive a copy of the license and are unable to
 * obtain it through the world-wide-web, please send an email
 * to license@zend.com so we can send you a copy immediately.
 *
 * @category   Zend
 * @package    Zend_Cache
 * @subpackage Zend_Cache_Frontend
 * @copyright  Copyright (c) 2005-2009 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 * @version    $Id: File.php 18951 2009-11-12 16:26:19Z alexander $
 */


/**
 * @see Zend_Cache_Core
 */
require_once 'Zend/Cache/Core.php';


/**
 * @package    Zend_Cache
 * @subpackage Zend_Cache_Frontend
 * @copyright  Copyright (c) 2005-2009 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 */
class Zend_Cache_Frontend_File extends Zend_Cache_Core
{

	/**
	 * Consts for master_files_mode
	 */
	const MODE_AND = 'AND';
	const MODE_OR  = 'OR';

	/**
	 * Available options
	 *
	 * ====> (string) master_file :
	 * - a complete path of the master file
	 * - deprecated (see master_files)
	 *
	 * ====> (array) master_files :
	 * - an array of complete path of master files
	 * - this option has to be set !
	 *
	 * ====> (string) master_files_mode :
	 * - Zend_Cache_Frontend_File::MODE_AND or Zend_Cache_Frontend_File::MODE_OR
	 * - if MODE_AND, then all master files have to be touched to get a cache invalidation
	 * - if MODE_OR (default), then a single touched master file is enough to get a cache invalidation
	 *
	 * ====> (boolean) ignore_missing_master_files
	 * - if set to true, missing master files are ignored silently
	 * - if set to false (default), an exception is thrown if there is a missing master file
	 * @var array available options
	 */
	protected $_specificOptions = array(
        'master_file' => null,
        'master_files' => null,
        'master_files_mode' => 'OR',
        'ignore_missing_master_files' => false
	);

	/**
	 * Master file mtimes
	 *
	 * Array of int
	 *
	 * @var array
	 */
	private $_masterFile_mtimes = null;

	/**
	 * Constructor
	 *
	 * @param  array $options Associative array of options
	 * @throws Zend_Cache_Exception
	 * @return void
	 */
	public function __construct(array $options = array())
	{
		while (list($name, $value) = each($options)) {
			$this->setOption($name, $value);
		}
		if (!isset($this->_specificOptions['master_files'])) {
			Zend_Cache::throwException('master_files option must be set');
		}
	}

	/**
	 * Change the master_file option
	 *
	 * @param string $masterFile the complete path and name of the master file
	 */
	public function setMasterFiles($masterFiles)
	{
		clearstatcache();
		$this->_specificOptions['master_file'] = $masterFiles[0]; // to keep a compatibility
		$this->_specificOptions['master_files'] = $masterFiles;
		$this->_masterFile_mtimes = array();
		$i = 0;
		foreach ($masterFiles as $masterFile) {
			$this->_masterFile_mtimes[$i] = @filemtime($masterFile);
			if ((!($this->_specificOptions['ignore_missing_master_files'])) && (!($this->_masterFile_mtimes[$i]))) {
				Zend_Cache::throwException('Unable to read master_file : '.$masterFile);
			}
			$i++;
		}
	}

	/**
	 * Change the master_file option
	 *
	 * To keep the compatibility
	 *
	 * @deprecated
	 * @param string $masterFile the complete path and name of the master file
	 */
	public function setMasterFile($masterFile)
	{
		$this->setMasterFiles(array(0 => $masterFile));
	}

	/**
	 * Public frontend to set an option
	 *
	 * Just a wrapper to get a specific behaviour for master_file
	 *
	 * @param  string $name  Name of the option
	 * @param  mixed  $value Value of the option
	 * @throws Zend_Cache_Exception
	 * @return void
	 */
	public function setOption($name, $value)
	{
		if ($name == 'master_file') {
			$this->setMasterFile($value);
		} else if ($name == 'master_files') {
			$this->setMasterFiles($value);
		} else {
			parent::setOption($name, $value);
		}
	}

	/**
	 * Test if a cache is available for the given id and (if yes) return it (false else)
	 *
	 * @param  string  $id                     Cache id
	 * @param  boolean $doNotTestCacheValidity If set to true, the cache validity won't be tested
	 * @param  boolean $doNotUnserialize       Do not serialize (even if automatic_serialization is true) => for internal use
	 * @return mixed|false Cached datas
	 */
	public function load($id, $doNotTestCacheValidity = false, $doNotUnserialize = false)
	{
		if (!$doNotTestCacheValidity) {
			if ($this->test($id)) {
				return parent::load($id, true, $doNotUnserialize);
			}
			return false;
		}
		return parent::load($id, true, $doNotUnserialize);
	}

	/**
	 * Test if a cache is available for the given id
	 *
	 * @param  string $id Cache id
	 * @return boolean True is a cache is available, false else
	 */
	public function test($id)
	{
		$lastModified = parent::test($id);
		if ($lastModified) {
			if ($this->_specificOptions['master_files_mode'] == self::MODE_AND) {
				// MODE_AND
				foreach($this->_masterFile_mtimes as $masterFileMTime) {
					if ($masterFileMTime) {
						if ($lastModified > $masterFileMTime) {
							return $lastModified;
						}
					}
				}
			} else {
				// MODE_OR
				$res = true;
				foreach($this->_masterFile_mtimes as $masterFileMTime) {
					if ($masterFileMTime) {
						if ($lastModified <= $masterFileMTime) {
							return false;
						}
					}
				}
				return $lastModified;
			}
		}
		return false;
	}

}

